Implementation - Converting Renewable Energies into Gas

The future global economy is likely to consume ever more energy, especially with the rising energy demand of developing countries such as China and India. At the same time, the tremendous risk of cl ...

The future global economy is likely to consume ever more energy, especially with the rising energy demand of developing countries such as China and India. At the same time, the tremendous risk of climate change associated with the use of fossil fuels makes supplying this energy increasingly difficult.

The Audi e-gas project represents the company's first step towards producing sustainable fuels. The company is currently building the world's first industrial-scale plant to convert CO₂ and renewable electricity into a synthetic natural gas that can be fed into the natural gas network. This power-to-gas technology opens up new possibilities for sustainable mobility and the energy economy of the future.

In the northern German town of Werlte in Emsland, the company is currently building the world's first industrial-scale plant to convert CO₂ and renewable electricity into a synthetic natural gas that can be fed into the natural gas network. This power-to-gas technology opens up new possibilities for sustainable mobility and the energy economy of the future.

It is operated by renewable electricity, e.g. from wind, solar power or biomass. With a rated input of around 6,000 kW, the plant will primarily procure electricity from wind power when there is short-term oversupply.

In the plant, the renewable electricity will first be converted to hydrogen (Audi e-hydrogen), the fuel for future fuel cell vehicles such as the Audi Q5 HFC, by means of electrolysis. However, the necessary hydrogen supply network is not yet in place. Audi uses another innovative process step to solve this problem. The hydrogen is combined with CO₂ in the methanation facility downstream of the electrolysis plant to produce synthetic renewable natural gas – Audi e-gas. From there, it can then be fed into the natural gas network and stored within that system.

The CO₂ comes from a biogas plant. The input material for the biogas plant is not energy crop plants, rather it is organic waste. This avoids any sort of competition with food production. The Audi e-gas facility uses the CO₂ as a feedstock for the fuel. Audi e-gas is thus a climate-neutral fuel – when burned in the engine, exactly the same amount of CO₂ is released as was previously bound at the e-gas plant.

The German energy industry could also benefit in the medium term from the concept of the Audi e-gas project, as it provides an answer to the unsolved question of how to store green power efficiently and independently of location. The potential of electricity-gas cogeneration to store large amounts of wind or even solar energy can provide powerful stimuli for the expansion of renewable energies. The Audi e-gas project can be easily implemented in all countries with existing natural gas networks.

Beginning in 2013, the plant in Werlte is projected to produce roughly 1,000 metric tons of methane a year, binding 2,800 metric tons of CO₂. This equates roughly to the quantity of CO₂ absorbed annually by 224,000 beech trees. That amount of renewably generated Audi e-gas could power for example 1,500 Audi A3 Sportback TCNG vehicles for 15,000 kilometers per year in CO₂-neutral driving.

The foundation stone for the Audi e-gas plant was laid in September 2012. As the owner, Audi is building the plant in collaboration with plant engineering contractor SolarFuel GmbH. Production of e-gas will begin in early 2013. The synthetic gas will then be fed into the public gas distribution system from summer 2013.

CO2-neutral mobility and the sustainable use of resources are objectives of Audi to realize its commitment to corporate responsibility. Alongside the purely usage phase, the company also takes into consideration the vehicle manufacturing and recycling processes as well as the complete fuel chain which is becoming increasingly important.

Reduce emissions from power generation by exploiting available options in natural gas, bioenergy, and wind power; at the same time, increase public sector R&D on new technologies including carbon capt ...

Reduce emissions from power generation by exploiting available options in natural gas, bioenergy, and wind power; at the same time, increase public sector R&D on new technologies including carbon capture and storage (CCS), photovoltaics, and nuclear fusion.